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US4192686A Expired / Lapsed US ⏱️ 0.0 years remaining

Compositions and method for inhibiting formation of explosive compounds and conditions in silvering concentrates for electroless deposition of silver

Assignee: Lilly London Inc
•
Filing: 1977-10-11
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Granted: 1980-03-11
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Expires: 1997-10-11
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Abstract

Abstract Potentially explosive mixtures which can form as a result of accidental contact between a concentrated aqueous solution of ammoniacal silver salt and a concentrated solution of a strong alkali are inhibited in an improved multi-part system for electroless deposition of silver on an activated surface by simultaneous admixture of the diluted parts thereupon. Accordingly, an improved method for inhibiting formation of explosive conditions and compounds in a mixture formed by contacting concentrated aqueous ammoniacal silver salt and a concentrated solution of alkali is provided, whereby an effective amount of an explosion inhibitor is provided either in combination with the ammoniacal silver salt, in which case sufficient extraneous ammonium ions are provided to stabilize the explosion inhibitor, or in the strong alkali, or a portion of the explosion inhibitor is provided in each of said ammoniacal silver salt and strong alkali. Conventional reducers for ammoniacal silver salt can be utilized together with said explosion inhibitor.

Inventors

  • 👤 Joseph F. Soltys

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 00:58
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/31; C23C18/42; C23C18/44; C09; C09K; C09K15/00; C09K15/04; C09K15/06

Claims Analysis

Total Claims: 35
Claim 1
Independent Claim 70 words
An improved method for inhibiting formation of explosive conditions or compounds in a mixture resulting from contact of (1) a concentrated aqueous solution of an ammonical silver salt and (2) a concentrated aqueous solution of a strong alkali, which comprises providing an effective amount of an explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms in at least one of said concentrated aqueous solutions (1) or (2).
Claim 2
Dependent Claim 70 words
An improved method for inhibiting formation of explosive conditions or compounds in a mixture resulting from contact of (1) a concentrated aqueous solution of an ammonical silver salt and (2) a concentrated aqueous solution of a strong alkali, which comprises providing an effective amount of an explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms in at least one of said concentrated aqueous solutions (1) or (2).
Claim 3
Dependent Claim 37 words
The method of claim 1 wherein said ammoniacal silver salt is ammoniacal silver nitrate, said strong alkali is sodium hydroxide and said polyhydric alcohol is selected from the group consisting of sorbitol, mannitol, arabintol, ribitol and xylitol.
Claim 4
Dependent Claim 66 words
The method of claim 1 wherein the total amount of said polyhydric alcohol provided is in a range of 25-60 g/l and an amount of conventional reducer sufficient to facilitate subsequent electroless plating of silver upon contact with said aqueous solution of strong alkali is also included with at least one of said concentrated aqueous solutions (1) or (2), provided said conventional reducer is compatible therewith.
Claim 5
Dependent Claim 38 words
The method of claim 1 wherein said explosion inhibitor is provided in said concentrated aqueous solution of ammonical silver salt and sufficient extraneous ammonium ions are also provided in said concentrated aqueous solution to stabilize said explosion inhibitor.
Claim 6
Dependent Claim 25 words
The method of claim 4 wherein said extraneous ammonium ions are provided by addition of ammonium nitrate to said aqueous solution of ammoniacal silver salt.
Claim 7
Dependent Claim 34 words
The method of claim 5 wherein said polyhydric alcohol is selected from sorbitol or mannitol provided in the range of 25-200 g/l and said ammonium nitrate is provided in a range of 10-200 g/l.
Claim 8
Dependent Claim 36 words
The method of claim 5 wherein said polyhydric alcohol is selected from sorbitol or mannitol and is provided in a range of 60-200 g/l and said ammonium nitrate is provided in a range of 16-80 g/l.
Claim 9
Dependent Claim 41 words
The method of claim 5 wherein polyhydric alcohol is selected from sorbitol or mannitol provided in a range of 25-200 g/l and said extraneous ammonium ions are selected from citric acid or ammonium citrate provided in a range of 5-100 g/l.
Claim 10
Dependent Claim 42 words
The method of claim 5 wherein said polyhydric alcohol is selected from sorbitol or mannitol provided in a range of 60-200 g/l and said extraneous ammonium ions are selected from citric acid or ammonium citrate provided in a range of 5-20 g/l.
Claim 11
Dependent Claim 57 words
The method of claim 5 wherein said extraneous ammonium ions are provided by addition to said concentrated aqueous solution of ammoniacal silver nitrate of an effective amount of ammonium citrate, citric acid, or a mineral acid compatible with said ammoniacal silver nitrate, whereby said extraneous ammonium ions required to stabilize said polyhydric alcohol are generated in situ.
Claim 12
Dependent Claim 19 words
The method of claim 1 wherein said explosion inhibitor is admixed with said concentrated aqueous solution of strong alkali.
Claim 13
Dependent Claim 25 words
The method of claim 1 wherein said explosion inhibitor is provided in both of said concentrated aqueous solutions of ammonical silver salt and strong alkali.
Claim 14
Dependent Claim 103 words
An improved multi-part system capable of effecting electroless deposition of silver by simultaneous admixture of diluted portions thereof on a work surface and protected against formation of explosive compounds or conditions in a mixture resulting from contacting the system parts, said system comprising the following parts: (A) a concentrated aqueous silvering solution comprising ammonical silver salt, an effective amount of explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms and sufficient extraneous ammonium ions to stabilize said polyhydric alcohol in said aqueous silvering solution and thereby prevent deterioration of the same, and (B) a concentrated aqueous solution of strong alkali.
Claim 15
Dependent Claim 103 words
An improved multi-part system capable of effecting electroless deposition of silver by simultaneous admixture of diluted portions thereof on a work surface and protected against formation of explosive compounds or conditions in a mixture resulting from contacting the system parts, said system comprising the following parts: (A) a concentrated aqueous silvering solution comprising ammonical silver salt, an effective amount of explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms and sufficient extraneous ammonium ions to stabilize said polyhydric alcohol in said aqueous silvering solution and thereby prevent deterioration of the same, and (B) a concentrated aqueous solution of strong alkali.
Claim 16
Dependent Claim 59 words
The system of claim 13 wherein a conventional reducer for said ammoniacal silver salt is included in at least one of said solutions A or B provided said conventional reducer is compatible therewith, said conventional reducer being included in an amount effective to improve depositions of metallic silver on said work surface upon admixture of solutions A and B.
Claim 17
Dependent Claim 21 words
The improved multi-part silvering system of claim 14 wherein said polyhydric alcohol is provided in a preferred range of 25-60 g/l.
Claim 18
Dependent Claim 74 words
The improved multi-part silvering system of claim 13 wherein said ammoniacal silver salt is ammoniacal silver nitrate, said polyhydric alcohol is selected from sorbitol, mannitol, arabintol, ribitol and xylitol and said extraneous ammonium ions are provided in said solution A by (1) addition of ammonium nitrate or ammonium citrate, or (2) by generation of said extraneous ammonium ions in situ by addition of citric acid, or mineral acids compatible with said ammoniacal silver salt.
Claim 19
Dependent Claim 83 words
An improved multi-part system capable of effecting electroless deposition of silver by simultaneous admixture of diluted portions thereof on a work surface and protected against formation of explosive compounds and conditions in a mixture resulting from contacting the system parts, said system comprising the following parts: (A) a concentrated aqueous silvering solution comprising ammonical silver salt, and (B) a concentrated aqueous solution of strong alkali and an effective amount of an explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms.
Claim 20
Dependent Claim 83 words
An improved multi-part system capable of effecting electroless deposition of silver by simultaneous admixture of diluted portions thereof on a work surface and protected against formation of explosive compounds and conditions in a mixture resulting from contacting the system parts, said system comprising the following parts: (A) a concentrated aqueous silvering solution comprising ammonical silver salt, and (B) a concentrated aqueous solution of strong alkali and an effective amount of an explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms.
Claim 21
Dependent Claim 60 words
The improved multi-part system of claim 17 wherein a conventional reducer for said ammoniacal silver salt is included in at least one of said solutions A or B, provided said reducer is compatible therewith, said conventional reducer being included in an amount effective to improve deposition of metallic silver on said work surface upon admixture of solutions A and B.
Claim 22
Dependent Claim 21 words
The improved multi-part silvering system of claim 18 wherein said polyhydric alcohol is provided in a preferred range of 25-60 g/l.
Claim 23
Dependent Claim 73 words
The improved multi-part system of claim 17 wherein said ammoniacal silver salt is ammoniacal silver nitrate, said polyhydric alcohol is selected from sorbitol, mannitol, arabintol, ribitol and xylitol and said extraneous ammonium ions are provided in said solution A by (1) addition of ammonium nitrate or ammonium citrate, or (2) by generation of said extraneous ammonium ions in situ by addition of citric acid, or mineral acids compatible with said ammoniacal silver salt.
Claim 24
Dependent Claim 58 words
The improved multi-part silvering system of claim 20 wherein said ammonical silver nitrate is provided in the range of 100-500 g/l of silver nitrate, said polyhydric alcohol is provided in the range of 25-200 g/l, said ammonium nitrate is provided in the range of 10-200 g/l and said citric acid is provided in the range of 5-100 g/l.
Claim 25
Dependent Claim 141 words
An improved multi-part system capable of effecting electroless deposition of silver by simultaneous admixture of dilute portions thereof on a work surface and protected against formation of explosive compounds and conditions in a mixture resulting from contacting the system parts, said system comprising the following parts: (A) a concentrated aqueous silvering solution comprising ammonical silver salt, a first portion of an explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms and sufficient extraneous ammonium ions to stabilize said polyhydric alcohol in said aqueous silvering solution and thereby prevent deterioration of the same, and (B) a concentrated aqueous solution of strong alkali and a second portion of said explosion inhibitor; wherein the total amount of said explosion inhibitor would be effective to inhibit formation of explosive compounds of conditions in a mixture resulting from contacting compositions (A) and (B).
Claim 26
Dependent Claim 141 words
An improved multi-part system capable of effecting electroless deposition of silver by simultaneous admixture of dilute portions thereof on a work surface and protected against formation of explosive compounds and conditions in a mixture resulting from contacting the system parts, said system comprising the following parts: (A) a concentrated aqueous silvering solution comprising ammonical silver salt, a first portion of an explosion inhibitor comprising a polyhydric alcohol having 4 to 6 carbon atoms and sufficient extraneous ammonium ions to stabilize said polyhydric alcohol in said aqueous silvering solution and thereby prevent deterioration of the same, and (B) a concentrated aqueous solution of strong alkali and a second portion of said explosion inhibitor; wherein the total amount of said explosion inhibitor would be effective to inhibit formation of explosive compounds of conditions in a mixture resulting from contacting compositions (A) and (B).
Claim 27
Dependent Claim 58 words
The system of claim 22 wherein a conventional reducer for said ammoniacal silver salt is included in at least one of said solutions A or B, provided said reducer is compatible therewith, said conventional reducer being included in an amount effective to improve deposition of metallic silver on said work surface upon admixture of solutions A and B.
Claim 28
Dependent Claim 21 words
The improved multi-part silvering system of claim 23 wherein said polyhydric alcohol is provided in a preferred range of 25-60 g/l.
Claim 29
Dependent Claim 74 words
The improved multi-part silvering system of claim 22 wherein said ammoniacal silver salt is ammoniacal silver. nitrate, said polyhydric alcohol is selected from sorbitol, mannitol, arabintol, ribitol and xylitol and said extraneous ammonium ions are provided in said solution A by (1) addition of ammonium nitrate or ammonium citrate, or (2) by generation of said extraneous ammonium ions in situ by addition of citric acid, or mineral acids compatible with said ammoniacal silver salt.
Claim 30
Dependent Claim 58 words
The improved multi-part silvering system of claim 25 wherein said ammoniacal silver nitrate is provided in the range of 100-500 g/l of silver nitrate, said polyhydric alcohol is provided in the range of 25-200 g/l, said ammonium nitrate is provided in the range of 10-200 g/l and said citric acid is provided in the range of 5-100 g/l.
Claim 31
Dependent Claim 40 words
The system of claim 13 wherein said conventional reducer is not compatible with said solutions A and said solution B and is provided in a separate solution C which is simultaneously admixed with both of said solutions A or B.
Claim 32
Dependent Claim 42 words
The improved multi-part system of claim 18 wherein said conventional reducer is not compatible with said solution A and said solution B and is provided in a separate solution C which is simultaneously admixed with both of said solutions A or B.
Claim 33
Dependent Claim 58 words
The improved multi-part silvering system of claim 20 wherein said ammoniacal silver nitrate is provided in the range of 100-500 g/l of silver nitrate, said polyhydric alcohol is provided in a range of 60-200 g/l, said ammonium nitrate is provided in a range of 16-80 g/l and said citric acid is provided in the range of 5-20 g/l.
Claim 34
Dependent Claim 40 words
The system of claim 22 wherein said conventional reducer is not compatible with said solution A and said solution B and is provided in a separate solution C which is simultaneously admixed with both of said solutions A or B.
Claim 35
Dependent Claim 58 words
The improved multi-part silvering system of claim 25 wherein said ammoniacal silver nitrate is provided in the range of 100-500 g/l of silver nitrate, said polyhydric alcohol is provided in the range of 60-200 g/l, said ammonium nitrate is provided in the range of 16-80 g/l and said citric acid is provided in the range of 5-20 g/l.

References Cited (Backward Citations)

US3983266A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-03-11 1983-09-10 1984-03-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-03-11 1987-09-10 1988-03-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-03-11 1991-09-10 1992-03-11 $7700.00 Window Closed / Lapsed

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